Answer:
False
Explanation:
Cleavage in zygote forms a hollow ball of cells known as a blastula. The blastocoel refers to the fluid-filled cavity present in the blastula stage of early embryonic development.
Blastula undergoes gastrulation during which some of the cells exhibit inward movement and form a sac. The blastopore refers to the opening of this sac present in the gastrula stage of embryonic development.
Blastopore of gastrula develops into the mouth in protostomes and becomes anus in deuterostomes.
Answer:
C: Take infected amphibians and assign them to two populations. Leave one population alone; inoculate the other with Jl. Measure the rate at which infection proceeds in both populations.
Explanation:
In scientific investigations, the best way to determine the effect of certain experimental factor on the population of study is to have a baseline for comparison. This is usually referred to as controlled experiment.
<em>In the case of the observation that chytrid infection in amphibians seems to be inhibited by Janthinobacterium lividum, the best way experimental design is to get a population of amphibians suffering from the disease, divide them into two groups and subject them to the same conditions except the introduction of Janthinobacterium lividum to the skin of one of the groups.</em>
<em>A suitable method can thereafter be employed to measure the rate at which infection proceeds in both population. If indeed, the bacterium has the capacity to inhibit the infection, the rate of infection in the group with the bacterium will be significantly less than that of the group without the bacterium. </em>
The correct option is C.
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The best answer to the question above would be the first statement. Cardiorespiratory endurance affects physical fitness in such a way that it increases the efficiency with which the body delivers oxygen and nutrients to its cells.